Como citar APA:
Macas, G., et al. (2024) Bovine herd evaluation of the dairy herd of the
faculty of agricultural sciences - Universidad Tecnica Luis Vargas Torres de Esmeraldas.
Repique, 6(2), 74-90
Vol. 6 Núm. 2
Julio - Diciembre 2024
e-ISSN: 2550-6676
pp 74-90
Bovine herd evaluation of the dairy herd of the faculty of
agricultural sciences - Universidad Tecnica Luis Vargas Torres
de Esmeraldas
Gladys Mercedes Macas Giler
*
Jeniffer Elizabeth Mera Romero
*
Ángel Fabricio Cedeño Boada
*
Viviana Antonia Chávez Cedeño
*
Abstract
This study was framed within the line of research of the Faculty of
Agricultural Sciences entitled: production, management and
sustainable development of agricultural, livestock and forestry
products with an ecosystem approach. In addition, it was aligned
with the sub-line of the Zootechnics career: comprehensive local,
regional and national livestock development and management. The
main objective was to evaluate the biometric characteristics of the
dairy herd belonging to the Faculty of Agricultural Sciences. 100%
of the cows that give birth were used as experimental units. The
study did not use an experimental design, it only used descriptive
statistics through quantitative and observational methods. The
* Universidad Técnica Luis Vargas Torres de Esmeraldas; gladys.macas@utelvt.edu.ec;
https://orcid.org/0000-0003-1375-789
* Universidad Técnica Luis Vargas Torres de Esmeraldas; jeniffer.mera@utelvt.edu.ec;
https://orcid.org/0009-0007-9560-2651
* Universidad Técnica Luis Vargas Torres de Esmeraldas; angel.cedeno@utelvt.edu.ec;
https://orcid.org/0000-0003-2316-8319
* Universidad Técnica Luis Vargas Torres de Esmeraldas ; viviana.chavez@utelvt.edu.ec;
https://orcid.org/0000-0002-8033-8081
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experimental variables were: Height of the haunch and withers,
Width of the rump and pelvis, length of the rump, depth of the
body, depth of the udder, height of the posterior insertion of the
udder cm, Diameter and length of the teats. The results obtained
were subjected to the following statistical tests: measures of central
tendency (means) and Pearson correlation analysis. The rump width
was 53.38±1.29 cm. The width of the pelvis was 20.08±0.67 cm, the
height of the udder insertion in the cattle was 18±1.52 cm. The
width of the rump and pelvis presented an average correlation of
0.58, where, by increasing one characteristic, the other would also
improve. The morphometric characteristics evaluated in the dairy
herd presented important values, where a desirable intermediate
height, intermediate depth, rump width and pelvis width favorable
in the production and reproduction of the cows were recorded.
Key words:
Measurements, Correlation, Bovinometry, Zoometry.
Evaluación bovinometrica del hato lechero de la facultad de
ciencias agropecuarias - Universidad Técnica Luis Vargas Torres
de Esmeraldas
Resumen
Este estudio se enmarcó dentro de la línea de investigación de la
facultad de Ciencias Agropecuarias titulada: producción, manejo y
desarrollo sustentable de los productos agrícolas, pecuarios y
forestales con enfoque de ecosistema. Además, se alineó con la
sub línea de la carrera de Zootecnia: desarrollo y manejo pecuario
integral local, regional y nacional. El objetivo principal fue evaluar
las características biométricas del hato lechero perteneciente a la
Facultad de Ciencias Agropecuarias. Se utilizó como unidades
experimentales el 100% de las vacas que presentan un parto. El
Gladys Mercedes Macas Giler, Jeniffer Elizabeth Mera Romero, Ángel Fabricio Cedeño
Boada, Viviana Antonia Chávez Cedeño
76
estudio no utilizó un diseño experimental, únicamente empleó
estadística descriptiva a través de métodos cuantitativos y
observacional. Las variables experimentales fueron: Altura del anca
y cruz, Ancho de grupa y de la pelvis, largura de la grupa,
profundidad del cuerpo, profundidad de la ubre, altura de la
inserción posterior de la ubre cm, Diámetro y largo de los pezones.
Los resultados obtenidos fueron sometidos a las siguientes pruebas
estadísticas: medidas de tendencia central (medias) y análisis de
correlación de Pearson. El ancho de grupa fue de 53,38±1,29 cm.
El ancho de pelvis fue 20,08±0,67 cm, la altura de la inserción de la
ubre en los bovinos fue de 18±1,52 cm. El ancho de grupa y pelvis
presentó una correlación media de 0,58, donde, donde al
incrementar una característica, mejoraría también la otra. Las
características morfométricas evaluadas en el hato lechero
presentaron valores importantes, donde se registró una estatura
intermedia deseable, profundidad intermedia, ancho de grupa y
ancho de pelvis favorable en la producción y reproducción de las
vacas.
Palabras clave:
Medidas, Correlación, Bovinometría, Zoometría.
Received : 21-04-2024
Approved: 18-05-2024
INTRODUCTION
In Ecuador, cattle raising is one of the most important activities that
have been developed and has contributed to the economic,
commercial and social development of the population. There are
several breeds for milk production, which are adapted to the
environmental conditions of the area and are the main source of
income for families engaged in cattle raising.
Currently one of the problems facing dairy cattle is the relationship
between body conformation and how this influences milk yield is of
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special interest to the dairy industry in seasonal countries, due to
the fact that milk producers usually judge the merit of dairy cows,
at least partially, on the basis of type or conformation (Davalos,
2016).
The lack of knowledge on dairy farms about linear classification
methods has not allowed for a good selection process, in order to
reproduce in our herd only specimens that have the best
characteristics and identify those that are undesirable from a
physical point of view (Riera et al., 2012).
The bovinometry represents a favorable tool to dimension the
conformation and physical structure of a bovine by means of
obtaining measurements, they acquire vital importance in dairy
cattle, since they have shown to have a great relationship with the
productive life cycle of a cow, basically because of their impact on
health, reason why it is essential to know the dimensions of an
animal.
The Faculty of Agricultural Sciences has cattle that have adapted to
the conditions of this environment, however, there is no information
and data to characterize these animals, and to determine the
phenotype of the cattle. Currently, genetic improvement programs
are not only focused on selecting animals with excellent
productivity, but also on functional individuals with good
conformation, which will allow longer-lived and more productive
animals (Velasquez & Alvarez, 2006).
For the above mentioned, the main objective of this research is to
evaluate the external conformation of the existing cattle population
in the dairy cattle program of the Faculty of Agricultural Sciences,
to generate data by own experience with reference, to be able to
select functional animals within a given herd, in addition it will allow
discarding those animals that present problems in their
Gladys Mercedes Macas Giler, Jeniffer Elizabeth Mera Romero, Ángel Fabricio Cedeño
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conformation predicting with a certain degree of accuracy to
functional animals in their conformation (Muñoz, 2017).
METHODOLOGY
The present investigation was carried out in the Milk Production
Cattle Program of the Faculty of Agricultural Sciences, which is
located in the Mutile enclosure of the rural parish of San Mateo.
The study lasted 30 days, during which time the respective bovine
measurements and data collection were carried out.
For the development of the research, a total of 12 animals were
used, representing 100% of the cows that calved.
The study did not use an experimental design, it only used
descriptive statistics through quantitative and observational
methods to determine morphological characteristics of the cattle
present in the milk program of the Faculty of Agricultural Sciences.
The experimental variables evaluated were the following:
• Height of haunch cm.
• Height at withers cm.
• Rump width cm.
• Pelvis width cm.
• Length of the rump cm.
• Depth of the body cm
• Height of the posterior insertion of the udder cm.
• Teat diameter cm.
• Teat length cm
The results obtained were subjected to the following statistical
tests:
• Measures of central tendency (means), Experimental error
(EE) and dispersion.
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• Pearson correlation analysis.
To take the height of Anca, it was measured with a metric wooden
zoo stick that has the measurements expressed in centimeters,
taking as reference the vertical distance from the highest point of
the rump to the animal's support plane (Muñoz, 2017).
Withers height was measured from the highest point to the
perpendicular distance from the measuring withers to the support
plane. The height is based on the actual measurement of the cow
at the withers.
To determine the width of the rump, measurements were taken
mainly from the front points of the hips and the midpoint of the hip
which was taken by using a metric bovine cane and the results were
expressed in centimeters.
The variable width of the pelvis was taken through the
implementation of a zoometric ruler expressed in centimeters,
which was placed under the tail, between the tips of the ischiums,
which will be a reference to inquire about the ease of calving that
each of the elements to be evaluated presented.
Depth of the Body is the maximum distance obtained by measuring
with the help of a tape measure or zoomometric cane from the top
of the back to the obligo (Muñoz, 2017).
Rump length is obtained by measuring the length between the tip
of the ilium to the tip of the ischium.
The height of the udder was measured taking as a point the base
of the vulva towards the udder ligament which is expressed in
centimeters, this variable also serves to indicate the amount of milk
produced by cows because if the udders are longer they produce
more milk than udders of medium to small size.
Gladys Mercedes Macas Giler, Jeniffer Elizabeth Mera Romero, Ángel Fabricio Cedeño
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Teat diameter, for the evaluation, the diameter in the middle part
of the teat was measured with the help of the caliper.
Teat length, for this variable was measured from the base of the
udder to the tip of the teat.
RESULTS
Weight
The average recorded for weight variable was 519.83±19.02 kg
(Table 1), a result higher than that reported by Serrano Alfonso,
(2009), who recorded an average of 509.60 kg when evaluating
Holstein cows, while Barragan & Botero, (2010), found an average
of 406 kg when evaluating the characteristics of bovine
measurements in females in pasture in the Gyr breed. The
differences found may be related to the age, breed, management
and feeding of the animals.
Height of rump
Ank height presented an average of 140.92±1.86 cm in cattle
(Table 1), results that are considered intermediate in the Linear
Classification System Holstein Association USA, (2005): where 130
cm is low, 140 cm is intermediate and 150 cm is high.
The Linear Evaluation System for Dairy Gyr Cattle and their
crossbreds states that it is desired that the haunch be high enough
to keep the udder off the ground. Ideal and Average = 136.5 cm
(Ramos, F et al 2010).
The results obtained are related to Zhicay, (2016), who when
evaluating the purebred Holstein breed reports a haunch height of
140.80 cm, as well as Muñoz, (2017), who records a value of 142.25
cm, in crossbred Holstein cows at the Tunshi Experimental Station
and higher than those evaluated by Zhicay, (2016), who also
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reported 131.79 cm, in crossbred Holstein cows, differences that
can be attributed to hereditary patterns and management
conditions.
Table 1.
Results obtained in the present investigation of
bovinometric measurements.
Variable
Media
E.E.
CV
Weight (kg)
519,83
19,02
12,67
Height of haunch (cm)
140,92
1,86
4,58
Withers height (cm)
136,67
1,3
3,31
Croup width (cm)
53,38
1,29
8,39
Pelvis width (cm)
20,08
0,67
11,52
Length of rump (cm)
50,58
0,68
4,65
Depth of body (cm)
72,08
1,66
7,99
Height of the posterior udder insertion (cm)
18
1,52
30,34
Teat diameter (cm)
2,25
0,21
31,78
Teat length (cm)
4,54
0,47
36,31
The withers height variable recorded an average of 136.67±1.30 cm
in the cattle of the dairy herd (Table 1), the average obtained
according to the Linear Classification System Holstein Association
USA, (2005), is intermediate in the classification range: 130 cm low,
142 cm intermediate, 154 cm high.
The results are related to Zhicay, (2016) and Muñoz, (2017), who
recorded an average of 139.73 cm and 139.70 cm respectively in
crossbred Holstein cows, the values reported in the researches
maybe due to what is stated by Zhicay, (2016), where he mentions
that purebred American cows are taller (150 cm) than crossbred
cows, due to the fact that crossbred cows are usually the product
Gladys Mercedes Macas Giler, Jeniffer Elizabeth Mera Romero, Ángel Fabricio Cedeño
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of a series of technically undefined crosses which are characterized
by being smaller in size.
For this variable, it is important to indicate that medium and tall
animals are more likely to keep the udder away from the ground,
which reduces injuries and facilitates milking operations (Nieto, et
al. 2021).
Rump width
The average recorded for the rump width variable was 53.38±1.29
cm (Table 1), in cattle, these values are higher than Muñoz, (2017)
and Avila, (2012), who when evaluating the crossbred Holstein
breed recorded a width of 47.90 cm and 41.11 cm respectively, the
differences may be related to the genetics of the animals.
In relation to the average obtained, it is considered desirable since
a wide rump, provides ease of calving, under the rump is the udder
and the wider the rump is generally projected in a cow with good
barrel and good intake capacity (Avila, 2012).
Pelvis width
The average recorded for the pelvis width variable was 20.08±0.67
cm (Table 1), these results according to the scale used by the World
Holstein Friesian Federation (WHFF): 1-3 Very narrow, 4-6
Intermediate, 7-9 Wide (2 cm for each point), allow inferring that
the evaluated cows have a wide pelvis which would facilitate calving
(Serrano, 2009).
The values obtained are lower than Muñoz, (2017), who when
evaluating the Holstein breed in the tropics recorded a pelvis width
of 38.76 cm, while Avila, (2012), reported in crossbred Holstein
cows 41.11 cm.
The differences found are probably due to what Avila, (2012)
mentioned, where he indicates that there are differences due to
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several factors, including genetics, breed, age and nutritional status
of the animals, factors that can influence the development and size
of the pelvis of each individual.
Pelvic conformation is an important consideration as it allows for
ease of calving; a wider pelvis provides more room for the calf to
develop properly and pass through the birth canal, which facilitates
the birthing process, thus reducing neonatal mortality and
morbidity (Rodriguez & Solano, 2020).
Rump length
For rump length, an average of 50.58±0.68 cm was obtained in
cattle (Table 1), the results are related to Serrano, A, (2009), who
when evaluating Holstein first cows, recorded an average of 50.19
cm. While Ramónez & Zhunio, (2017), when evaluating the
morphometric characterization and zoometric indexes of the
existing Holstein bovine racial groups in the western cantons of the
province of Azuay, report 46.6 cm value lower than those obtained
in the present research.
The variations may be due to gestation, the number of calving in
cows and all the processes in which the calving channel grows and
there is a lengthening of the pelvis area. That characteristic is
related to the dorsal udder support (Luz & Almeida, 2015).
The length of the rump is an indicator of the conformation and body
structure of the animal. A rump of adequate and balanced length is
desirable, since it contributes to a good harmony and proportion in
the animal's body, indicates good muscle and bone development
in the region of the hindquarters, which is relevant for both
production and general functionality of the bovine, (Centeno &
Betanco, 2017).
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Body depth
Body depth in cattle was 72.08±1.66 cm (Table 1), a value that
differs from Zhicay, (2016), who when evaluating the Holstein breed
recorded an average of 80.59 cm.
It is important to keep in mind that the measurement of body depth
is one of the many criteria used to evaluate the conformation and
quality of a bovine, and is used in conjunction with other parameters
to evaluate the performance and productive potential of animals,
as it is directly related to the animal's ability to eat large amounts
of forage. It is the distance from the loin to the lowest part of the
cow's abdomen. Counts range from very shallow bodies (1-2). To
extremely deep body (8-9), (Hidalgo, 2014).
Height of the posterior udder insertion.
The height of udder insertion in cattle was 18±1.52 cm (Table 1),
values close to those indicated by Luz & Almeida, (2015), with 15
cm, in Gyr females.
The values obtained are close to the desired values according to
the Linear Evaluation System of Dairy Gyr cattle and their
crossbreeds where an average of 15 cm is established, thus, the
shorter the perineum, the greater the height of the posterior udder.
The ideal is an udder whose implantation is located four toes from
the vulva. Higher udders allow a greater production capacity (Luz &
Almeida, 2018).
For Muñoz, (2017), high udders seen from behind allow a better
production capacity without the need for depth, for the above
mentioned, it can be stated that the dairy herd of the faculty has a
satisfactory udder rear height, improving productive qualities.
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Teat diameter
The average recorded for this variable was 2.25±0.21 cm (Table 1),
the results obtained are related to those of Nieves, (2016), who
when evaluating the Holstein breed recorded an average of 2.2 cm,
while Hernandez, et al (2017), reports an average of 3.36 cm value
higher than those obtained. The differences can be attributed to
age and lactation stage.
The average recorded is in the desired range according to Luz &
Almeida, (2018), establishes ideal teats with an intermediate
diameter of 3.3 cm downwards,
In relation to this variable it is important to indicate that excessively
thick teats impair milking and suckling, being therefore undesirable
for the breed.
Teat length
The average recorded for this variable was 4.54±0.47 cm (Table 1),
values that are within the allowed range according to the Brazilian
Association of Dairy Gyr Breeders (ABCGIL), where a length should
be from 5 to 7 cm (Luz & Almeida, 2018).
The results obtained are related to Muñoz, (2017), with 5.91 cm,
and differ from Hernandez, et al (2017), with 6.23 cm, when
evaluating teat morphology in dairy cows in the tropics. Variations
in teat morphometry evaluated may be related to heredity, age and
lactation number (Nieves, 2016).
In view of the values obtained, it is necessary to indicate that teat
size is very important to prevent infections, since it avoids the fall of
the teat cups in mechanical milking, and facilitates, in turn, manual
milking and the possibility of draining residual milk; and
additionally, it allows greater accessibility to milk suction by the calf
during suckling, (Hernández, et al 2017).
Gladys Mercedes Macas Giler, Jeniffer Elizabeth Mera Romero, Ángel Fabricio Cedeño
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Genetic correlations of the female bovine population of a calving
of the dairy cattle program.
Body weight compared to rump width, presented a high positive
correlation of 0.85 this correlation was higher than that presented
by Contreras et al., (2020) which obtained mean of 0.58. The results
obtained indicate that as the weight of the cows increases, the
width of the rump increases.
Body weight compared to pelvis width presented a mean
correlation of 0.6, a value lower than those presented by Bermudez,
(2012), who recorded a high correlation between body weight and
pelvis width of 0.97 in female Holstein cattle. These results allow
the author to state that increasing the weight of females in the
pelvis width would increase.
Withers height and haunch height presented a high correlation with
0.78 cm, results that imply an improvement where increasing one
variable would improve the other based on the desired phenotype.
Withers height and rump width presented a high correlation of 0.62,
which was higher than that presented by Contreras et al. (2020),
which presented an average correlation of 0.55 in Criollo cattle. The
results found show that there is a positive association between the
characteristics.
The rump width compared to pelvis width, had a mean correlation
of 0.58, while Herrera et al., (2022); in their study on Romosinuano
and Costanoan cows with horns, also obtained a mean correlation
of 0.54. The values obtained and investigated indicate a positive
association between the variables, where increasing one
characteristic would also improve the other.
The diameter of the front teat in relation to the diameter of the rear
teat had a high correlation of 0.87. Alcívar & Lucas, (2022), in their
study on Gyr cattle, also presented a high correlation of 1.
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Therefore, increasing the diameter of the front teat also increases
the diameter of the rear teats.
For the variables front teat length and rear teat length, it presented
a high correlation of 0.86, a value that agrees with that reported by
Cortez et al., (2021), who when evaluating daily milk production
from udder morphometry in Holstein Friesian dairy cows, obtained
a high correlation of 0.86 for the variables front and rear teat length.
In view of these correlations, Nieves, M. (2008), indicates that teat
length influences flow rate and milk production; therefore, it should
be of prime importance in breeding programs.
CONCLUSIONS
The morphometric characteristics evaluated in the dairy herd
presented important values, where an intermediate desirable
height, intermediate depth, rump width and pelvis width favorable
for the production and reproduction of the cows were recorded.
In relation to udder conformation, the evaluated group presented
good height of the posterior insertion of the udder, desirable depth
that favor milk production. Teat morphology in terms of diameter
and length presented favorable sizes for a mechanical milking
system.
It was found that cow weight conditions rump and pelvis width, in
relation to height at the withers it was also evidenced that cows at
greater height provide the height of the rump and width of the
rump.
The width of the rump also favors the width of the pelvis, a positive
aspect in the gestation and calving of the cows. The diameter and
length of the front teats also favor the increase of the length and
diameter of the rear teats.
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